The present invention relates to conveyor systems, and particularly to a conveyor table having selectively enabled conveyor elements.
Conveyor systems are commonly used to convey articles to and through a processing station wherein various processing operations may be performed, such as a working operation on the article, an inspection operation on the article, or the like. Frequently, it is necessary or desirable that the article be firmly retained in place at the time the processing operation is formed. This may require moving the article from the conveyor system to a table equipped with a retainer arrangement, such as mechanical clamping elements, a vacuum system, or the like, for firmly retaining the article on the table during the performance of the processing operation, and then returning the article to the conveyor system after the processing operation has been completed.
An object of the present invention is to provide a conveyor table for use in a conveyor system to produce advantages in the above respects.
According to the present invention, there is provided a conveyor table, comprising: a supporting construction having a first supporting surface for supporting articles to be conveyed; a plurality of conveyor elements mounted to the supporting construction and defining a second supporting surface for supporting the articles to be conveyed; an actuator for selectively moving one of the supporting surfaces with respect to the other to selectively enable either the first supporting surface defined by the supporting construction to support the articles, or the second supporting surface defined by the conveyor elements to support the articles; and a drive for driving the conveyor elements to convey the articles in a predetermined direction when the articles are supported by the second supporting surface defined by the conveyor elements.
According to further features in all the preferred embodiments of the invention described below, the actuator moves the second supporting surface defined by the conveyor elements with respect to the first supporting surface defined by the supporting construction; the conveyor elements being movable either to an operative position projecting from the first supporting surface to engage and convey the articles in the predetermined direction, or to an inoperative position retracted within the first supporting surface. More particularly, in the described preferred embodiments, the first supporting surface is a flat surface formed with a plurality of spaced parallel recesses; the conveyor elements being movable either to an operative position projecting from the flat surface to engage and convey the articles in the predetermined direction, or to an inoperative position retracted within the recesses.
It will be appreciated, however, that in some applications of the invention, it may be desirable to move the first supporting surface (the supporting table construction) with respect to the second supporting surface (the conveyor elements) to selectively convey or not convey the articles.
As will be more particularly described below, a conveyor table constructed with the foregoing features can be used for conveying articles to and through a processing station without requiring removal of the articles from the conveyor system at the time the articles are being processed. Thus, the articles may be conveyed along the table by moving the conveyor elements to their operative projecting positions, and may be processed while on the table by moving the conveyor elements to their inoperative retracted positions within the recesses.
Several embodiments of the invention are described below for purposes of example.
In one described embodiment, the conveyor elements are driven parallel to the recesses and are effective, when in their operative projecting positions, to convey the articles parallel to the recesses. In this embodiment, the conveyor elements are preferably closed-loop belts.
A second embodiment is described wherein the conveyor elements are rotary elements rotated along axes parallel to the recesses and effective, when in their operative projecting positions, to convey the articles in the direction perpendicular to the recesses. In this embodiment, the rotary elements are preferably rollers. In the embodiment described below, they are elongated rollers such that each roller occupies a substantial part of the length of the respective recess. The conveyor elements; however, they could be in the form of a plurality of short rollers spaced from each other and interconnected by a shaft extending along the respective recess.
A further embodiment is described wherein both types of conveyor elements are provided in the table, thereby enabling the article to be selectively conveyed either parallel to the recesses or perpendicular to the recesses.
Further features and advantages of the invention will be apparent from the description below.